Polyol Dehydrogenases of Gluconobacter oxydans

SUMMARY Gluconobacter oxydans (suboxydans) contains at least six different polyol dehydrogenases, each with unique structural specificity. These have been defined as a nicotinamide adenine dinucleotide phosphate-specific xylitol dehydrogenase, an NAD- linked D-erythro dehydrogenase, an NAD-linked D-xylo dehydro- genase, an NADP-linked D-&X0 dehydrogenase, and two different NADP-linked gluconate dehydrogenases. One or more L-erythro dehydrogenases (with the Bertrand- Hudson specificity) are attached to the cytoplasmic membrane. The oxidations by growing acetic acid bacteria are mainly due to polyol dehydrogenases localized on the cytoplasmic membrane. The formulation of the rule of Bertrand and Hudson is the result of the unique oxidative properties of the dehydrogenases att,ached to the cytoplasmic membrane of the acetic acid bacteria. Acknowledgment-We are grateful to Dr. N. K. Richtmyer for generous gifts of heptitols and heptuloses. REFERENCES 1. BERTRAND, G., Ann. chim. et phys.,